Cells Flashcards
compare and contrast the similarities and differences between plant cells and animal cells [6]
Similarities:
Both have nucleus;
Both have cell membrane / mitochondria / RER/SER (any 2);
Differences:
Plant cell have cell wall but animal do not have
Plant cell have chloroplast but animal do not have
Plant cell have a large central vacuole but animal cells have small and numerous vacuoles
Identify a named organelle that can only be seen under electron microscope and state its functions [2/3]
State a specific organ / type of tissue where it has abundance of the organelle mentioned and explain your answer. [2]
Golgi apparatus:
stores, chemically modifies and packages manufactured proteins in vesicles for
secretion out of the cell
stomach [1] the stomach cells produces and secretes abundance of digestive enzymes
(pepsin) for digestion of proteins. Enzymes are proteins in nature [1]
OR
Mitochondria:
site of aerobic respiration where glucose is oxidised to release energy for cellular activities
muscles [1] requires lots of energy released from aerobic respiration by mitochondria for contractions of muscles for movement. [1]
liver [1] requires lots of energy released from aerobic respiration by mitochondria for high cellular activities / high metabolic rate in detoxification /deamination.
Small intestine [1] requires lots of energy released from aerobic respiration by mitochondria for absorption of digested nutrients into blood stream via active transport.
OR
Rough Endoplasmic Reticulum:
To transport proteins synthesized by ribosomes to the Golgi apparatus for secretion out of the cell stomach [1] the stomach cells produces and secretes abundance of digestive enzymes (pepsin) for digestion of proteins. Enzymes are proteins in nature [1]
OR
Smooth Endoplasmic Reticulum:
synthesises fats and steroids and convert harmful substances into harmless substances via detoxification
liver [1] liver is responsible for detoxification of harmful substances into less harmful substances thus its cells will have abundance of SER. [1]
Use a named example, describe the relationship between cells, tissue and organ. [5]
The heart is an example of an organ that carries out the function of circulating blood in the human body. [1]
The heart consists of different tissues to perform a specific function [1] such as the muscle tissue, connective tissue, blood tissues and nerve tissues. [1]
These tissues are a group of similar cells that work together to perform a specific function. [1] example muscle tissue contains muscle cells with which synchronize their contractions to bring about the contraction of the tissue. [1]
OR
The leaf is an example of an organ that carries out the function of making glucose for the
plant through photosynthesis. [1]
The leaf consists of different tissues to perform a specific function [1] such as the
palisade tissue, spongy mesophyll tissue, xylem tissues and phloem tissues. [1]
These tissues are a group of similar cells that work together to perform a specific function. [1] example palisade tissue contains palisade mesophyll cells with chloroplasts to trap sunlight to make glucose by photosynthesis [1]
describe how the protein is synthesized and transported in the cell for secretion. [6]
Proteins made by the ribosomes attached to the rough endoplasmic reticulum (RER) enter into RER. [1]
The manufactured proteins are transported in vesicles that are pinched off from the RER and are transported to the Golgi apparatus. [1] The vesicles fuse with the Golgi apparatus and release the contents into the Golgi apparatus. [1]
The Golgi apparatus stores and chemically modifies the proteins made by RER and packages them into vesicles. [1] The secretory vesicles containing the modified proteins are pinched off from the Golgi apparatus. [1]
The vesicles then move to the cell membrane and fuse with the membrane. This releases the contents in the vesicles into the outside of the cell. [1]
based on the special adaptations of the type of cells, describe and explain why:
a) red blood cells have limited metabolic activities and lifespan. [3]
lack of nucleus [1/2], no regulation of cellular activities / no growth and repair, thus limited lifespan[1]
no mitochondria[1/2], no aerobic respiration to release energy for metabolic activities [1]
b) root hair cells will lose its ability to absorb water and mineral salts when poisoned by cyanide. [3]
cyanide inhibits mitochondria [1] no aerobic respiration to release energy for active transport of mineral salts into cell sap against conc gradient [1]. Water potential in cell sap is higher than in soil soln, net movement of water molecules out of cell sap via osmosis[1]
